Global Patent Index - EP 0238822 A3

EP 0238822 A3 19890426 - COMPOSITE QAM-PSK TRANSMISSION SYSTEM

Title (en)

COMPOSITE QAM-PSK TRANSMISSION SYSTEM

Publication

EP 0238822 A3 19890426 (EN)

Application

EP 87101752 A 19870209

Priority

  • JP 513687 A 19870114
  • JP 2495086 A 19860208

Abstract (en)

[origin: EP0238822A2] Responsive to a first and a second main data signal and a subdata signal, a multilevel modulator produces a composite modulated signal which comprises a quadrature amplitude modulated component modulated by the first and the second main data signals and represented by a radius on a phase plane and a phase modulated component modulated by the subdata signal are represented by a clockwise and a counterclockwise shift on the phase plane. A multilevel demodulator carries out an inverse operation to reproduce the composite modulated signal into first and second reproduced main data signal and a reproduced subdata signal.

IPC 1-7

H04L 27/00; H04B 17/00

IPC 8 full level

H04L 27/34 (2006.01); H04L 27/36 (2006.01); H04L 27/38 (2006.01)

CPC (source: EP US)

H04L 27/3461 (2013.01 - EP US); H04L 27/363 (2013.01 - EP US); H04L 27/3827 (2013.01 - EP US)

Citation (search report)

  • [A] EP 0094058 A2 19831116 - NEC CORP [JP]
  • [A] US 4404532 A 19830913 - WELTI GEORGE R [US]
  • [A] US 4525846 A 19850625 - BREMER GORDON [US], et al
  • [A] IEEE TRANSACTIONS ON COMMUNICATIONS, vol. COM-30, no. 8, August 1982, pages 1918-1925, IEEE, New York, US; Y. SAITO et al.: "16 QAM carrier recovery PLL for service-channel transmission using FSK additional modulation"

Designated contracting state (EPC)

DE FR IT NL SE

DOCDB simple family (publication)

EP 0238822 A2 19870930; EP 0238822 A3 19890426; EP 0238822 B1 19930512; AU 589084 B2 19890928; AU 6858787 A 19870813; CA 1268828 A 19900508; DE 3785781 D1 19930617; DE 3785781 T2 19930902; US 4751478 A 19880614

DOCDB simple family (application)

EP 87101752 A 19870209; AU 6858787 A 19870206; CA 529181 A 19870206; DE 3785781 T 19870209; US 1240587 A 19870209